Modular acoustical panel assemblies are well known for providing sound absorbing and attenuating walls, ceilings and floors which are easy to construct and build with a minimum of effort and skill.
For example, in U.S. Pat. Nos. 4,038,796 (the '796 patent); 4,074,489 (the '489 patent); and 4,106,255 (the '255 patent), improved acoustical modular panel assemblies are described which are easily and quickly assembled and disassembled without the need for specialized tools. Each of these assemblies includes a plurality of identical modular panels which are adapted to be assembled together to form the desired room element (e.g. wall). In assembling the panels together to form a flat wall, each panel is aligned and oriented with respect to an adjacent panel so that the side edges of the respective panels are in confronting and spaced relationship. Each panel includes a substantially flat body and at least one tongue which extends along a side edge of the panel substantially parallel to and spaced from the body so as to form a channel therebetween which is open along one side of the panel. In the '255 patent, the tongue is provided with a flange portion which extends from the tongue away from the channel.
The panel assemblies described in each of these patents also include connector means for connecting the panels together in an acoustically tight manner. These connector means include two preferably U-shaped connector members, each comprising two substantially parallel side plates and a web or strap connected to and supporting the side plates. The first connector is located such that its web or strap spans the gap between the open ends of the two opposing end channels of two adjacent panels, and its parallel side plates extend respectively into one or the other of the channels in a tight fitting relationship therewith. The web or strap of the first connector thereby acts as the bridging element between the adjacent panels. The second connector, on the other hand, is located within the gap between the two opposing end tongues of the two adjacent panels, such that its two parallel side plates bear against the adjoining tongues and its web or strap spans the distance between the closed ends of the two opposing end channels of the two adjacent panels. These connectors may be maintained in place by either the frictional/resilient engagement of the parts, or by mechanically removably affixing the connectors together.
Various connector configurations are also disclosed for connecting the side edges of panels whose side surfaces are aligned and oriented at a right angle, so that the panels can form a corner. One such connector comprises a body having a substantially L-shaped cross-section wherein both legs of the L have a thickness corresponding to the thickness of the adjacent flat panels. The corner is then formed by inserting the respective legs of the L-shaped connector into one or the other of the two end channels of the two adjacent panels.
The advantages and disadvantages of panel assemblies of the type just described are well known. The modular nature of the panels facilitates assembly and disassembly, and reduces costs. The connectors provide structural integrity, a vertical load bearing column between each pair of panels, and a raceway between panels for the accommodation of plumbing lines, electrical cables, communication lines, and the like. Also, the sound absorption and attenuation achievable with modular wall constructions of the types just described is generally good.
The joints between the acoustic panels are not totally sealed, however, so the structure cannot be categorized as totally sound proof. In addition, rooms constructed of such panels tend to provide little barrier to electrical radiation entering or exiting the room. Unfortunately, however, many applications exist wherein a barrier substantially impervious to both sound and electrical radiation, particularly in the radio frequency range, is required. For example, numerous very delicate medical procedures require the maintenance of a sound free environment and an electrical radiation free environment, so that sensitive measuring devices can function without any outside sound and/or electrical radiation interference. Similarly, in some situations where information security is of great importance, it is desirable to provide an enclosure in which activities may take place without fear of outside observation or detection of the actions, sounds, or electronic activities occurring within the enclosure. In the latter situation, it is also generally important that the walls, ceilings and floors making up the enclosure be suited for periodic inspection, so as to be able to assure the absence of sound and/or electrical listening devices within or adjacent to the walls, ceilings and/or floors.